相关论文: Detection of the Direct Hyperfine Transition of Po…
The hyperfine structure splittings are determined for the lowest bound state in the positron-helium ion $e^{+}[^3$He$(2^3S)]$ and $e^{+}[^4$He$(2^3S)]$. In particular, we have fond that for the $e^{+}[{}^3$He$(2^3S)]$ ion one can observe…
The ground state hyperfine splitting values of high Z hydrogenlike ions are calculated. The relativistic, nuclear and QED corrections are taken into account. The nuclear magnetization distribution correction (the Bohr-Weisskopf effect) is…
Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental program at the next generation of lepton accelerators. In the context of the Hadronic Physics program at the Jefferson Laboratory…
The single photon annihilation contributions for the positronium ground state hyperfine splitting are calculated analytically to order $m_e\alpha^6$ using NRQED. Based on intuitive physical arguments the same result can also be determined…
We use photo-electrons as a non-contact probe to measure local electrical potentials in a solid-oxide electrochemical cell. We characterize the cell in operando at near-ambient pressure using spatially-resolved X-ray photoemission…
A rigorous evaluation of the two-photon exchange corrections to the hyperfine structure in lithiumlike heavy ions is presented. As a result, the theoretical accuracy of the specific difference between the hyperfine splitting values of H-…
The ground state hyperfine splitting values and the transition probabilities between the hyperfine structure components of high Z lithiumlike ions are calculated in the range $Z=49-83$. The relativistic, nuclear, QED and interelectronic…
Exploiting an approach similar to the R-matrix theory, the diffusion Monte Carlo method is employed to compute phase shifts and threshold cross sections for the elastic scattering of o-positronium off light atoms. Results are obtained for…
The Double Chooz experiment measures the neutrino mixing angle $\theta_{13}$ by detecting reactor $\bar{\nu}_e$ via inverse beta decay. The positron-neutron space and time coincidence allows for a sizable background rejection, nonetheless…
We calculate the contribution from the two-photon exchange on the neutron to the hyperfine splitting of S energy levels. We update the value of the neutron Zemach radius, estimate total recoil and polarizability corrections. The resulting…
We present the complete result for the ${\cal O}(\alpha^7m_e)$ one-photon annihilation contribution to the hyperfine splitting of the ground state energy levels in positronium. Numerically it increases the prediction of quantum…
The possibility of positronium detection at radio wavelengths is investigated in detail. For orthopositronium, the fine structure lines of the n = 2 level (1.62 cm, 2.30 cm and 3.48 cm) may be probably detected by radiotelescopes of next…
The frequencies of transitions between hyperfine levels of ground-state atoms can be measured with exquisite precision using magnetic-resonance techniques. This makes hyperfine transitions ideal probes of QED effects originating from the…
We provide an accurate evaluation of the two-photon exchange correction to the hyperfine splitting of S energy levels in muonic hydrogen exploiting the corresponding measurements in electronic hydrogen. The proton structure uncertainty in…
Zero-field splitting (ZFS) parameters are fundamentally tied to the geometries of metal ion complexes. Despite their critical importance for understanding the magnetism and spectroscopy of metal complexes, they are not routinely available…
The OH$^+$ ($X ^3\Sigma^-$) radical cation has been investigated by combining a 4 K 22-pole ion trap apparatus with high-resolution IR and THz radiation sources. Applying different types of action spectroscopic methods, the fundamental…
The results of a new search for positronium decays into invisible final states are reported. Convincing detection of this decay mode would be a strong evid ence for new physics beyond the Standard Model (SM): for example the existence of…
The contribution of pseudoscalar pole diagrams to the hadronic light-by-light corrections of order alpha^3 E_F to the ground state hyperfine splitting in hydrogenic atom is calculated in the pseudoscalar pole terms approximation. The vector…
Events with tagged photons in the process of electron-positron annihilation into hadrons are considered. The initial state radiation is suggested to scan the hadronic cross section with the energy. QED radiative corrections are taken into…
A detailed quantum-electrodynamic calculation of muon pair creation in laser-driven electron-positron collisions is presented. The colliding particles stem from a positronium atom exposed to a superintense laser wave of linear polarization,…